In a present day DC fuel quantity gauge system as used on aircraft and the like, wherein a probe capacitor is used to sense the fuel level in the fuel tank, the common practice is to provide three conductors in the aircraft wiring between the tank unit and the signal conditioner by means of which the output signal from the tank unit is processed to indicate the quantity of fuel in the tank. One type of fuel quantity gauge system in current use today is shown in U.S. Pat. No. 3,747,407, entitled Probe Mounted Electronics for a Fuel Gauge System, issued July 24, 1978, to Irwin Wallman, the applicant herein. In such a fuel quantity gauge system, one of these conductors is used to conduct the AC voltage signal from signal generating means such as a Lo-Z oscillator to the probe capacitor and the other two lines for the DC negative and positive return signals fed to the signal conditioner. As is well known, weight is a major consideration in an aircraft structure and any weight saving in an aircraft is an on-going effort. Obviously, even a saving in aircraft wiring without a reduction in function is viewed as highly desirable not only from the weight standpoint, but from the cost standpoint as well.